chore(location): add validation for description property in PlaceIndex class (#30974)

### Issue # (if applicable)

N/A

### Reason for this change
Add validation for PlaceIndex description, similar to #30648, #30682, and #30711 .



### Description of changes
Add validation and unit tests for description.


### Description of how you validated changes
Add unit tests.


### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: mazyu36

packages/@aws-cdk/aws-location-alpha/lib/place-index.ts

@@ -29,6 +29,9 @@ export interface PlaceIndexProps {
   /**
    * A name for the place index
    *
+   * Must be between 1 and 100 characters and contain only alphanumeric characters,
+   * hyphens, periods and underscores.
+   *
    * @default - A name is automatically generated
    */
   readonly placeIndexName?: string;
@@ -175,6 +178,10 @@ export class PlaceIndex extends PlaceIndexBase {
   public readonly placeIndexUpdateTime: string;
 
   constructor(scope: Construct, id: string, props: PlaceIndexProps = {}) {
+    if (props.description && !Token.isUnresolved(props.description) && props.description.length > 1000) {
+      throw new Error(`\`description\` must be between 0 and 1000 characters. Received: ${props.description.length} characters`);
+    }
+
     if (props.placeIndexName && !Token.isUnresolved(props.placeIndexName) && !/^[-.\w]{1,100}$/.test(props.placeIndexName)) {
       throw new Error(`Invalid place index name. The place index name must be between 1 and 100 characters and contain only alphanumeric characters, hyphens, periods and underscores. Received: ${props.placeIndexName}`);
     }

packages/@aws-cdk/aws-location-alpha/test/place-index.test.ts

@@ -17,6 +17,34 @@ test('create a place index', () => {
   });
 });
 
+test('create a place index with description', () => {
+  new PlaceIndex(stack, 'PlaceIndex', {
+    description: 'my-description',
+  });
+
+  Template.fromStack(stack).hasResourceProperties('AWS::Location::PlaceIndex', {
+    DataSource: 'Esri',
+    IndexName: 'PlaceIndex',
+    Description: 'my-description',
+  });
+});
+
+test('creates a place index with empty description', () => {
+  new PlaceIndex(stack, 'PlaceIndex', {
+    description: '',
+  });
+
+  Template.fromStack(stack).hasResourceProperties('AWS::Location::PlaceIndex', {
+    Description: '',
+  });
+});
+
+test('throws with invalid description', () => {
+  expect(() => new PlaceIndex(stack, 'PlaceIndex', {
+    description: 'a'.repeat(1001),
+  })).toThrow('`description` must be between 0 and 1000 characters. Received: 1001 characters');
+});
+
 test('throws with invalid name', () => {
   expect(() => new PlaceIndex(stack, 'PlaceIndex', {
     placeIndexName: 'inv@lid',